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In general, function names have the same rules for variables, so they must begin with a letter or

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an underscore and cannot contain spaces or other presentation characters yet.

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So now I'm going to write some functions integer my function here an integer like my function.

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And when we do the integer it is.

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This is the illegal and the compiler compiler will or will not compile here will not compile.

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Here.

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And.

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Uh, as I said earlier, they must begin with a letter or an underscore character and cannot contain

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spaces, as you can see here, or other plantation characters, for example, like Toad comma here,

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they cannot contain any punctuation characters for.

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So following the general principle of self documenting code, you shall name the function according

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to what it does.

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So there is one exception, and these are the special functions used to provide overloads for operators,

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which is mostly punctuation symbols.

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So these functions have a name in the form here.

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For example the multi here where the.

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Mold is like describing the function which will will multiply the two values one by one.

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So operators are one example of overloading here so you can overload any function that is used the same

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name, but provide implementations with different parameter types or different parameter numbers.

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We can make it like that.

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For example, integer multiple.

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We can make multiply.

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We can multiply three numbers one by one.

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Here, for example l h as integer or h as if you make it like that or just make it integer, for example.

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Actually they will return the same value.

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This is just a different writing in C++ here.

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As you can see, we're going to get error because they are the two same function.

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As you can see, the redefinition of multi, multi, multi are.

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So if we make add another parameter integer x l x, we're going to make the overloading function here

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and we're going to return the return the LCS multiplied by an error and multiply and multiply it by

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the x h as here.

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And if you make it like that, a standard c out.

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See here and here, the mold, we're going to multiply.

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We're going to call this here eight or 910.

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So in this case, the multiply function will fill this court here.

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This court will call this function because this takes parameters and where we gave this function to

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parameters.

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If you make it like that, this is going to call the the third function, the second function here that

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we have three parameters and we are calling this function.

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So and this named the function overloading here.

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As we can see here, we multiplied the tree numbers one by one here.

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So.

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We have function parameters, the function here.

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They may not have any parameters like this.

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Here, for example, we can create a mute function, but with that parameters like this.

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But they let us just create without parameters.

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But we'll have the return value.

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So in which case the case is the function is the fate defined with a pair of empty parenthesis like

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this here, for example.

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So a function, the function definition must give the type and name of the parenthesis parameters between

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parenthesis like this here.

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So.

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In many cases, the functions will have a fixed number of parameters, but you can write functions with

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a variable number of parameters.

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So you can also define functions with the default values or some of the parenthesis.

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So sum of parameters.

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So in effect a providing a function that overloads itself on the number of parameter parameters passed

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to the function.

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So variable argument list and default arguments will be covered later in this course here.

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We can also make the this specify the exceptions in C++ function here.

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The functions also can be marked to indicate whether they will throw an exception.

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So more details about exceptions will be given in next lecture.

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But there are two syntax you need to be aware of.

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So earlier versions of C++ allowed you to use the trough specified for.

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Specified on the function three ways.

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Firstly you provide a comma separated list of types of the exceptions that may be shown by code in the

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function here.

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And the second, you can provide an ellipsis like this here.

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Ellipses or, uh, which means that the function may prove an exception.

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And thirdly, you can provide an empty pair of parenthesis, which means that the function will not

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prove an exception.

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So the syntax here throw in exceptions to exceptions.

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Rule looks like this, for example.

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We're going to specify the exceptions.

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For example, overflow of overflow error and.

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Do we going to make, for example, do something which potentially.

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May overflow flow.

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So the trough specified has been deprecated in C++ 11.

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As you can see, the compiler will say the dynamic exception specified for overflow of error is deprecated.

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Consider using no accept false.

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Instead here we can change ignore accept files so it froze specified has been deprecated in C++ is largely

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because the ability to indicate that the type of function was not useful.

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So however, the version of Shrove that indicates that no exception will be thrown was found to be useful

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because it enables the compiler to optimize code by providing no code infrastructure to handle expectations.

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Here are exceptions here, so the C++ 11 retains this behavior with no except specified and the Knox

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except specified.

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Here, we can delete it this false here and with no access specified, we're going to check.

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Check the parameter and handle overflow appropriately.

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Here.